Difficulty in swallowing, leading to a decreased ability to move food and liquid from the mouth to the stomach, is referred to as dysphagia. Oropharyngeal dysphagia is divided into two primary phases: 1) oral phase swallowing impairments, in which the patient has difficulty moving the prepared food or liquid (referred to as a "bolus") to the pharynx; and 2) pharyngeal phase swallowing impairments, in which the patient encounters difficulty moving the bolus through the pharynx into the esophagus.
A patient suffering from either type of dysphagia may encounter medical complications, such as aspiration and dehydration. Aspiration, wherein all or part of the bolus penetrates the airway below the level of the vocal folds, is commonly encountered by patients whose dysphagia results from cognitive impairment. Impairments in attention, judgement and memory may preclude such individuals from using safe swallowing techniques. Thus, while the motor skills for swallowing thin liquids may be present, the patient may not remember to take small sips or to appropriately monitor his rate of intake, resulting in aspiration. Dehydration resulting from dysphagia often occurs in patients with severe oral motor deficits, as their reduced oral motor function may cause profuse oral spillage while drinking.
A variety of techniques are presently employed in an attempt to insure that dysphagic patients receive adequate hydration. Liquids thickened with a commercial thickening agent are often recommended as an alternative to thin liquids for dysphagic patients who do not self-regulate the size and rate of liquid intake. Thickened liquids, however, are generally not as desirable to patients as thin liquids, due to taste and texture alteration. The undesirable quality of thickened liquids may lead to reduced consumption. Alternatively, thin liquids may need to be administered by trained personnel thus adding to the costs in solving this problem. While conventional straws may also be used to deliver thin liquids to dysphagic persons, they too may also present significant problems. For example, use of such straws is not appropriate for dysphagic persons with decreased cognition since they cannot monitor the rate or the amount of liquid swallowed. Additionally, oral motor impairments may lead to a difficulty in sucking liquid through a traditional straw because of a reduced lip seal around the straw.
It has been determined that the risk of choking by dysphagic patients may be reduced by drinking with a chin-down head position. Accordingly, therapeutic drinking cups designed to promote such a chin-down head position have been developed and used. One such cup (a "Nosey Cup") includes a cut-out for the patient's nose so that the cup can be tipped to a drinking position with the chin down. A so-called "Dysphagia Cup" has also been developed, which is internally and externally contoured to promote drinking with a chin down head position. While these devices may prevent choking in dysphagic patients, they do not in any way control the rate or the amount of intake of the liquid.
Thus, while equipment and techniques have been developed for assisting dysphagic patients, they are not entirely satisfactory.